Researchers from the US and Norway have developed a genomic technique that may be used to map epigenetic marks across the genome using fewer cells, which could benefit cancer research.

A research project, led jointly by Bing Ren at Ludwig Cancer Research in San Diego and Arne Klungland of the University of Oslo, describes their application of a method to unravel a key mystery of the earliest stage of development. The new technique, mChIP-seq, which maps specific chemical (“epigenetic”) modifications made to the protein packaging of DNA using a small population of cells, is also likely to be important for cancer research.

“The key lesson we learned was that the genes that are destined to be turned on specifically in the fertilized egg are covered by this unique chromatin domain structure,” says Ren. “Those marks have to be removed by specialized enzymes to activate the zygotic genome. This mark is a mechanism for the oocyte to influence which genes in the zygote are activated. It is an epigenetic mechanism for the passage of information from the maternal oocyte to the zygote.”

The ability to map “epigenomes” using such a small number of cells will be valuable to cancer research, since the epigenetic landscape is dramatically rearranged in cancer and contributes to phenomena driven by small subpopulations of cells, such as drug resistance and metastasis.